The invention relates to a transmission for motor vehicles with internal combustion engines, especially farm tractors. In such a transmission it is possible to shift under load from one speed to another speed, an during a change of speed to transfer uninterrupted power from the drive shaft.
In known transmissions of this type (German OS 32 28 353, FIG. 3) friction clutches are disposed on two secondary shafts between a secondary shaft and a main gear group and a secondary of an inner gear group. The two friction clutches must be large enough to transmit torque of the drive motor increased by the torque transmission of the first or second gear step of the main gearing group.